ASP.NET & Outlook 2003 ?

[Nakah]

Hi,
I have made an assembly that access to Outlook 2003 through
Microsoft.Interop.Office.Outlook assembly. My library works fine with
Windows applications. However, when I try to use it with ASP.NET
applications, I have this error :

Access is denied.
Description: An unhandled exception occurred during the execution of the
current web request. Please review the stack trace for more information
about the error and where it originated in the code.

Exception Details: System.UnauthorizedAccessException: Access is denied.

ASP.NET is not authorized to access the requested resource. Consider
granting access rights to the resource to the ASP.NET request identity.
ASP.NET has a base process identity (typically {MACHINE}\ASPNET on IIS 5 or
Network Service on IIS 6) that is used if the application is not
impersonating. If the application is impersonating via <identity
impersonate="true"/>, the identity will be the anonymous user (typically
IUSR_MACHINENAME) or the authenticated request user.

To grant ASP.NET write access to a file, right-click the file in Explorer,
choose "Properties" and select the Security tab. Click "Add" to add the
appropriate user or group. Highlight the ASP.NET account, and check the
boxes for the desired access.

I have tried <identity impersonate="true" userName="MyMachine\MyUser"
password="p@Ssword"/> but I have still the same error.
Can anybody help me please ?